a) Field of the Invention
This invention relates to a tamper-proof sealing plug assembly comprising, in combination, a gasket sized to fit into a valve outlet of a pressurized bottle, a tamper-proof sealing plug for closing the valve outlet to prevent dust from entering the valve outlet, and a security seal for giving a visible indication whenever the plug and the gasket are removed.
b) Brief Description of the Prior Art
Security seals comprising a one-piece moulded flexible strap having a locking mechanism integral at one end and at least one tooth at its other free end to make this free end irreversibly insertable into the locking mechanism, are well known and commonly used for industrial applications. The strap forms a closed loop when its free end is inserted into the locking mechanism and this loop may be mounted around an object, for example the neck of a money bag, or between two elements in order to protect said object from being tampered with or said elements from being separated.
In U.S. Pat. Nos. 4,588,218; 4,697,833 and 5,116,091, flexible straps are disclosed, which have a protrusion or stud at one end and a locking mechanism at the other end. This mechanism includes internal fingers for irreversibly receiving the protrusion inside the housing.
In U.S. Pat. No. 5,183,301, there is disclosed a flexible strap having a locking mechanism with a passageway at one end, and a pointed free end that is insertable through the passageway. There are facilities on the strap and in the passageway, which permit the insertion of the strap into the passageway but which also prevent the strap from being withdrawn out of the passageway. The strap must be broken in order to remove it from the passageway.
In U.S. Pat. No. 4,940,268, there is disclosed a flexible strap having a fastener attached at one end and a small catch defined in the same end of the strap. The strap is foldable into a ring to engage the catch. The fastener can also be received in the catch and when it does, it may be forcingly engaged into a series of holes in the strap.
Hitherto, it has also been common to have a plastic sealing cover or the like for securely sealing the top of a bottle to ensure that the top has not been opened or tampered with in any way.
U.S. Pat. No. 4,550,842 describes a seal for protecting the sterile contents of bottles used in blood transfusions against tampering or contamination. The sealing cover comprises a container-cover area and a pull-tab area. The container-cover comprises an upper layer of plastic film impervious to bacteria to which is bonded another layer of orientated film which promotes tearing when the container-cover is removed with the pull-tab. An adhesive material is bonded to the orientated film in order to engage and seal the top of the bottle.
Just like these bottles of sterile solution, pressurized gas--or liquid--containing bottles with tubing connected thereto through an outlet valve, such as oxygen bottles as used in hospitals, should also be kept securely sealed before their use, for a number of reasons.
First, in order to insure that the tubing stays connected to the outlet valve of these bottles, an airtight joint or gasket could be used for sealing the valve outlet of the bottle, while leaving an opening in the outlet.
Secondly, dust or other particles may enter the bottle through the valve outlet between the time of filling-up the bottle and that of using the bottle for the first time. Therefore, there would certainly be an advantage in having some sort of closure placed over the valve outlet in order to close this outlet.
Finally, problems may arise when people cannot tell whether or not a bottle has already been used, or more importantly whether the bottle has been tampered with. Therefore, there would also be an advantage in having some sort of security seal which would provide the user with a visual indication if the bottle had been opened and/or had been tampered with.